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Evidence

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verify/: The blind first review of the binary totient lead as it stood on 2026-10-03 and its distinct grade, which records pass and assigns no tier.


The entry point recomputes v2(ΦN)v_2(\Phi_N) for 1≤N≤1071\le N\le10^7, where ΦN=∑n≤Nφ(n)2N−n\Phi_N=\sum_{n\le N}\varphi(n)2^{N-n}, records the indices at which v2(ΦN)−log⁡2Nv_2(\Phi_N)-\log_2N reaches a new maximum or exceeds 0,1,2,30,1,2,3, checks that every record arises through a carry tie v2(φ(N))=1+v2(ΦN−1)v_2(\varphi(N))=1+v_2(\Phi_{N-1}), counts the excess-positive indices 16≤N≤10716\le N\le10^7, those with 2v2(ΦN)>N+22^{v_2(\Phi_N)}>N+2, lists the ones with 2v2(φ(N))+2>N+22^{v_2(\varphi(N))+2}>N+2, counts the one-large-prime windows defined below, and certifies a prefix of the regular continued fraction of S=∑φ(n)2−nS=\sum\varphi(n)2^{-n} from the bounds ΦM/2M≤S≤(ΦM+M+2)/2M\Phi_M/2^M\le S\le(\Phi_M+M+2)/2^M with M=40000M=40000. Run it from the repository root:

sh
uv run --no-sync python wiki/research/leads/totient_binary_series/evidence/main.py

The default is the full declared domain; --quick uses N≤106N\le10^6 and M=4000M=4000 with its own fixed expectations. Both modes recompute everything from the totient and prime-factor sieves, read no files and write none, and exit nonzero on any failed obligation, including under python -O. The observed full run takes about ten seconds. The accumulator holds ΦN\Phi_N modulo 2642^{64}, so a valuation is exact whenever it is below 6464; the run checks that the largest observed valuation, 2929, is below the cap. The failure protocol was checked by mutating one expected hit count and, after the extension, one expected window count in scratch copies; each produced a named failed obligation and exit code 11.

The fixed expectations are the observed results stated on the owning page: the record list (16,4),(28,6),(64,10),(88,12),(2146743,28),(2786632,29)(16,4),(28,6),(64,10),(88,12),(2146743,28),(2786632,29) of pairs (N,v2(ΦN))(N,v_2(\Phi_N)); hit counts 72,45,21,972,45,21,9 at excess thresholds 0,1,2,30,1,2,3 over 16≤N≤10716\le N\le10^7; 7171 excess-positive indices in the same range, of which exactly 64,204,512,163264,204,512,1632 satisfy 2v2(φ(N))+2>N+22^{v_2(\varphi(N))+2}>N+2; 240240 one-large-prime windows, the last at N=31790N=31790, with truncated-run statistic 2020 over N≥215−1N\ge2^{15}-1; a certified prefix of 1175911759 partial quotients beginning 1;2,1,2,1,1,2,1,121;2,1,2,1,1,2,1,12 with largest quotient 1553115531 at index 70557055; and 60186018 decimal digits in the denominator of the last common convergent, which bounds the denominator of any rational value of SS because SS lies in the interval between the two bounds and hence in the cylinder of the common prefix. Record comparisons, threshold tests and the excess-positive and certificate conditions use integer comparisons; logarithms appear only in descriptive output. The empirical valuation distribution is printed as an observation and is not checked. This is author-checked finite coverage of a stated domain; it supplies no statement about all NN, no standing for the target, and no independent review.

What the counts mean

The owning page proves that a dyadic rational value S=a/2vS=a/2^{v} forces 2v2(ΦN)≤N+22^{v_2(\Phi_N)}\le N+2 once N−v>log⁡2(N+2)N-v>\log_2(N+2), so each excess-positive index excludes the exponents v<N−log⁡2(N+2)v<N-\log_2(N+2), and infinitely many would exclude all of them. The finite count 7171 says nothing about infinitely many. The page also proves that a residue class on which 2m∣ΦN2^m\mid\Phi_N holds for every sufficiently large member forces 2m−2∣φ(n)2^{m-2}\mid\varphi(n) at every positive member nn, so an excess-positive index that such a class could deliver must satisfy 2v2(φ(N))+2>N+22^{v_2(\varphi(N))+2}>N+2. The list of the four indices meeting this necessary condition is a finite observation about the indices found, not a statement about the classes themselves. The [[research/leads/totient_binary_series/arithmetical_windows/classification|stronger classification]] proves separately that only (n,m)=(5,3)(n,m)=(5,3) can have actual divisibility, excess 2m>n+22^m>n+2, and an eventual whole-progression certificate together. Thus the four retained indices are candidates only for the coarser filter, and all fail the full class criterion. The checker retains that weaker diagnostic; its finite scan is not the proof of the classification.

An integer is called one-large-prime for a threshold JJ when it has exactly one distinct prime factor above JJ. If n=sqan=sq^a with ss JJ-smooth and q>Jq>J prime, then φ(n)=φ(s)qa−1(q−1)\varphi(n)=\varphi(s)q^{a-1}(q-1). The label describes a factorization pattern, not the general availability of exact factorization or of cancellation information. The window of NN is N+1,…,N+JN+1,\dots,N+J with J=⌈log⁡2(N+2)⌉J=\lceil\log_2(N+2)\rceil, a lower bound for the block length needed by the stated crude-tail certificate.

The script computes the largest and second-largest distinct prime factors of every integer up to 107+2410^7+24, controlled against 257257, 258=2⋅3⋅43258=2\cdot3\cdot43 and 264=23⋅3⋅11264=2^3\cdot3\cdot11. It reports the count and last index of full one-large-prime windows. Its additional run statistic is explicitly truncated: in the block 2J−1−1≤N≤min⁡(2J−2,L)2^{J-1}-1\le N\le\min(2^J-2,L), it scans a run starting at N+1N+1 only as far as min⁡(2J−2,L)+J\min(2^J-2,L)+J, where LL is the run's declared limit. The maximum of these truncated lengths for N≥215−1N\ge2^{15}-1 is 2020 when L=107L=10^7. No claim about longer unscanned extensions is needed for the full-window test. The absence of full windows above N=31790N=31790 is a fact about this finite range only.

Why the denominator exclusion follows

Let p/qp/q be the convergent at the end of the common prefix and let p′/q′p'/q' be its predecessor. The closed cylinder has endpoints p/qp/q and (p+p′)/(q+q′)(p+p')/(q+q'), in the order determined by parity, and ∣pq′−p′q∣=1|pq'-p'q|=1. The script checks that determinant and uses exact rational comparisons to place both tail bounds strictly between these endpoints. Every rational strictly inside the cylinder is (pu+p′v)/(qu+q′v)(pu+p'v)/(qu+q'v) for coprime integers u>v≥1u>v\ge1. The mediant endpoint has u=v=1u=v=1; the convergent endpoint p/qp/q is treated separately. The determinant shows that the displayed numerator and denominator are coprime. Its denominator is therefore at least qq; the convergent endpoint has denominator qq as well. This justifies the retained lower bound without inferring irrationality from a finite prefix.

Separate interpolation certificates

The [[research/leads/totient_binary_series/integer_interpolation/evidence/_index|integer interpolation evidence]] has its own entry point and retained exact inputs. It checks nine least full-image endpoints and all 36 specified central-zero target solutions, including their weighted full-tail costs. Its computation account gives the domain, commands and failure controls. The entry point on this page does not run those checks. Neither finite product establishes the uniform interpolation-cost estimate needed for irrationality.